Red nucleus cells have a variety of dendritic appendages, some of which are specialized to receive particular synaptic inputs (like the glomerular spines in the distal dendrites which receive cortical input) and others are not. This is known because of a TEM-HVEM study done in the middle 1980s. Recently, it was discovered that the number and distribution of these appendages changes during development, but it is difficult to distinguish the different types in the light microscope. We wanted to try using the IVEM for this purpose. During a visit to the NCMIR, several tomographic reconstructions of red nucleus dendrites were obtained. These are currently being analyzed.